This invention is directed to the construction of a watch case, and particularly the hatch cover and hatch opening construction in the back of a watch having a battery therein.
Some types of modern watches are powered by batteries. These batteries power the primary horological timekeeping element and power the display. Of course, it is necessary to periodically replace the battery in order to keep the watch running.
In some battery powered watches, the entire back is removed. In these watches the back may either be snapped into place or screwed into place. With this arrangement, the watch must be constructed so that when the back is removed, the horological equipment therein is retained in place in the case by another structure. When the back is screwed in place, it is equipped with spanner wrench recesses so that an appropriate spanner wrench can be employed for turning the back. When the back is a snap-in type, then a very narrow groove is presented. A knife or other sharp instrument is engaged in the groove and the back is snapped off.
Similarly, instead of removing the entire back, the back may be equipped with battery hatch openings with battery hatch covers therein. In this way, only the battery hatch cover need be removed to replace the battery, while the watch back stays in place to retain the horological equipment within the watch case. Prior battery hatch covers have been either screwed into place or snapped into place. The screw-type battery hatch covers are equipped with spanner wrench recesses so that by application of an appropriate spanner wrench these battery hatch covers can be removed. The prior snap-in battery hatch covers have been difficult to remove because they present no substantial approach and the opening attempt must be made with a very thin tool.